Exposing Postgres port externally

Can anyone assist with the exposure of the postgress database port to external connection. I have the following configured but it is not working.

--------------pg_hba.conf----------------------------

local all all md5
host all all {MYMACHINESIPADDRES}/32 trust
host all all 127.0.0.1/32 md5
host all all ::1/128 md5
host all all 0.0.0.0/0 password

------IPTABLES------
-A INPUT -p tcp -m tcp --dport 5432 -m state --state NEW,ESTABLISHED -j ACCEPT
-A OUTPUT -p tcp -m tcp --sport 5432 -m state --state ESTABLISHED -j ACCEPT